Electrical connector



Dec. 21, 1954 l-| ELLIOTT ET 2,697,820

ELECTRICAL CONNECTOR Filed Oct. 16. 1953 How/Awe: A. Jomv M4 mm BY A/vrrv'cwy J MAW/1m Cur-mm? H. Kom

I? TTOP/Vi United States Patent ELECTRICAL coNNEcron Howard A. Elliott, Detroit, Clilford H. Kain and John Matcrka, Royal Oak, and Anthony J. Taormina, Detroit, Mich, assignors to Essex Wire Corporation Application October 16, 1953, Serial No. 386,542

1 Claim. (Cl. 339-256) This invention relates to terminals for electrical conductors and in particular to an improved female connector for use with spade type male terminals.

Inherent in the selection of a connector of this type by design engineers is the factor of replaceability. The connection made is not expected to be permanent, and frequent disconnections and reconnections are anticipated. This making and breaking of the connection requires that the connector have certain physical properties that might otherwise not be required. It must first of all be sufiiciently resilient to permit a manual make and break, it must resist permanent deformation and maintain its resil iency after repeated connections and disconnections, and it must provide for good electrical contact. In addition, a connector of this type is a mass production item which requires that the connector accommodate the minute inescapable variations associated with such production and still exhibit the aforementioned characteristics.

The present invention provides in particular an improved female terminal which makes possible a. substantial increase in the life expectancy of such a connector when exposed to frequent connection and reconnection as described above.

The specification refers to the drawings made a part hereof wherein:

Fig. 1 is a top elevation of the terminal stamping.

Fig. 2 is a top elevation of a finished terminal, with male spade terminal.

Fig. 3 is a side elevation of the terminal.

Fig. 4 is an end elevation of the terminal.

Fig. 1 shows the one piece character of the terminal prior to final forming. The portion to the left of the necked down section consisting of tail portions 11 and 12 indicates a means for attaching the terminal to a wire conductor. The tails are wrapped around the conductor for fastening purposes. This section is only illustrative however, and any means of attachment to a conductor is envisaged.

The area to the right of the necked down section 10 of Fig. 1 is subjected to final finishing steps as indicated by other views except for the main portion or, floor, in dicated generally at 16. V

The edges 13 are bent normal to the floor of the terminal to form strength ribs as indicated in Figs. 2 and 3. The ribbing serves in a well known manner to strengthen the area 26 contained by the necked down portion 10 and the shoulders 14 against bending. In the case where the terminal is attached to a wire conductor, the area 26 provides space for welding the strands of the conductor to the terminal.

The edges 15 are rolled away from the floor of the terminal in a circular manner to form semi-tubular sections as illustrated by Fig. 4. Particular attention must be given to this tubular structure as it is believed that this is a basic feature of the invention and contributes largely to the remarkable success of this terminal. By rolling the edge of the terminal way from the plane of the floor any distorting force applied to the edge 15 is distributed uniformly over a long length of material. There is no point of stress concentration and as a result no localization of a force sufiicient to exceed the elastic limit of the material. Any force applied to the edge 15 as on the insertion of the male spade 25 resolves into a force trying to straighten out the circle or, in other words, tends to uniformly force the section 20 back into the plane of the floor. Due to the uniform distribution of applied forces this unique spring structure provides a high pressure electrical connection even after repeated insertions of a male terminal.

In addition to providing a good electrical connection through high contact pressure the present terminal also provides for the removal of oxide film or other matter at a contact interface to insure an electrical connection of high efliciency. Side 15 angularly approaches floor 16 so that upon insertion of a spade terminal one edge of said side 15 gouges into and scarfs out the blade so that a true metal to metal interface is achieved.

Additional spring force is achieved by use of the V- slot 21. The apex of the V is in the direction of an entering spade terminal 25 and as a result the tongue 22, contained by the legs of the V, can be bent upwardly as a leaf spring. The spade terminal is inserted between the rolled edges 15 and the tongue 22 cooperatively exert yielding pressure on the spade. The selection of a substantially V shaped slot is based upon the requirement for considerable sturdiness in the tongue portion to accommodate repeated flexing and to provide sufficient spring force. In order to obtain such sturdiness in the tongue, the distance between the ends of the slot must be relatively great. The legs of the V can be shortened or lengthened thereby lessening and increasing the distance between the ends as required.

A raised detent is positioned as at 23 to engage a suitable cavity 24 in the spade terminal (Fig. 4). This provides semi-locking of the connector. To disconnect the terminal, it is necessary to provide sufiicient force to depress the tongue 22 thereby unlatching the connector.

Having thus described my invention, I claim:

An electrical connector for receiving a spade type terminal comprising a floor portion, two opposing sides of the floor rolled and doubled back in a circular manner, a substantially V shaped slot in said floor the apex of which is in the direction of an entering spade terminal, the tongue of said V-slot being bent upwardly to cooperate with the edges of said circularly bent sides in exertin z ieldable pressure on a s ade type terminal inserted therebetween, a detent centrally disposed in said tongue for cooperating engagement with a cavity in the spade terminal.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 462,914 Pilkington Nov. 10, 1891 1,158,930 Klinger Nov. 2, 1915 2,046,734 Freysinger July 7, 1936 2,499,296 Buchanan Feb. 28, 1950 2,540,037 Vough Jan. 30, 1951 2,579,739 Hayes Dec. 25, 1951 2,600,190 Batcheller June 10, 1952 

